Inspired by a 1939 British propaganda poster meant to bolster morale during World War II, The Big Bang Theory Keep Calm T-Shirt is Sheldon's version of keeping a stiff upper lip, especially when sarcastically interacting with Leonard.

We use this shirt for boating, as our boat is named "Bazinga" and we were recently boarded by the US Coast Guard and we both had these shirts on; and we did not have the registration for our boat on the boat. Thankfully the one US Coast Guard Personal had a sense of humor about "Bazinga" and did not site us as a result of our boat's name and our matching Keep Calm and Bazinga Shirts. They were well worth the money spent on them :-)